WITH salary_total AS (
        SELECT
            emp_no,
            SUM(salary) AS salary
        FROM
            salaries
        WHERE
            to_date = '9999-01-01'
        GROUP BY
            emp_no
    )
SELECT
    emp_no,
    salary,
    SUM(salary) OVER (ORDER BY emp_no) AS running_total
FROM
    salary_total;